Gyratory valve for hydraulic pumps or motors



3 Sheets-Sheet l V u llI I'll-III.

L. T. STOYKE ETI'AL GYRATORY VALVE FOR HYDRAULIC PUMPS OR MOTORS Filed Dec. 10, 1949 Dec. 25, 1951 Dec. 25, 1951 L. T. STOYKE arm.

GYRATORY VALVE FOR HYDRAULIC PUMPS 0R MOTORS 3 Sheets-Sheet 2 Filed Dec. 10, 1949 INVENTORS. l 5iyie Dec. 25, 1951 1.. T. STOYKE EI'AL GYRATORY VALVE FOR HYDRAULIC PUMPS 0R MOTORS 3 Sheets-Sheet 5 Filed Dec. 10, 1949 INVENTORS zwg rszz TZACQ Patented Dec. 25, 1951 UNITED STATES PATENT OFFICE GYRATORY VALVE FORHYDRAULIC PUMPS OR MOTORS Ludwig T. Stoyke and Bruce H. Mosbacher, Rock ford, IlL, assignors to Sundstrand -Machine Tool 00., a corporation of Illinois.

Application December 10, 1949; Serial No. 1323292 9 Claims (Cl. 103-473)".

This'invention relates to improvements in fluid:

pumps or motors and more particularly to a gyratory typevalvei'for use in multiple outlet fluid pumps or multiple inlet fluid motors.

It is the general object of this invention to produce a gyratory type 'valvefor use in a fluid pumpmor motor of improved construction and performance.

It is a more specific-objector this invention to producer a permissiblyv, rotatable gyratory type valve,xfor..use inxa fiuid motor or in a multiple outlet fluid pump having a plurality of annular- 1y." arranged cylinder ports andidischarge ports,

iniwhichthe valve is adapted sequentially and" separately to. connect the cylinder ports with a predetermined difierent one of :the discharge ports.

A furthertobjectof this invention is to produce a valve of. the. type'described in the preceding paragraph .having a perforated valving. rim, that is, to provide a plurality ofopenings through the rim and located along the valving line, the openings being so proportioned as to effectively pre vent cross-porting.

Another object of the invention is to provide a valve as just described with a plurality of openings so shaped and-proportioned'as to obtain maximum flow area and so locatedas to prevent cross-porting.

Other and further. objects of. the invention will be apparent fromuth'e following description and" accompanying drawings in which Fig. 1 is a longitudinal section through a fluid. pump housing and discharge manifold embodying.

theinvention;

Fig. 2 is an enlarged section along line 2-2 of Fig. 1;

Fig. 3 is a section taken along linex3-3-0f.

Fig. 2;

Fig.4 is a section taken along line 4-4 of Fig. 1; and

Fig. 5 is a fragmentary View of a valving rim embodying the optimum shape of openingstherethrough. 1

While the. invention is susceptible of. various modifications and alternative constructions, it

is herein shown and will hereinafter be described":

in a preferred embodiment. It is not intended; however, that the invention is to be limitedthereby to the specific constructiondisclosed. Onthe contrary, it is intended to cover. all modifications" and alternative constructions falling: within J'theu spirit and scope of the inventionuasdefined in theappended claims;

. As illustrated in the: drawings; the pump; comz-l Hit andrfrom the cylinders tor-a plurality of discharge ports zone: of; which :1atter-:ports is proa vided-for each 'ofithercylindersi 13. The cylinder block t I 2V is generally. annular. in

form-:and hasanintegralilanga2l positionedbe tween the casingksections' l0 :and i -l I, the casing sections and i flangeobeing secured together by a pluralityljof b0lts1.-2:2 The-cylinder: block is pro-1 videdavith 'a cylindricalrrecesstiniits right hand xendiiasshownin Fig.1) to form .alcylindrical.

valve chamber: 23 having opposedparallel tend.- faces 24* and i In-this chamber and against these faces, the valve device I l 8. isnlocated;

The shaft: I 6 is: rotatably: mounted i within :the casing and to thisiend -there:are-provided a roller bearing its-and a ball bearingi zl at the lefthandi end of the; casing; and a lOllelw bearing 281" supported in thewcylinderibloclcvll which bearings carry-ithewshaft; The Wobbler= devices! 1 comprises an H inner-i ring 1 member 29'.=-whioh issv pivotally.

mounted on the shaft l6 by means ofi'a piniwexe tending, therethr'ougha The wobbler includes: an

outer ring u 3 l:- carried on -the inn'eriring by means: of roller; bearings? 32 and thrust bearing 32a' and i isarrangedwvith'v a fiat end vface 33in position to engage-the adjacenti convex: ends; of. thes pistons M11 Aswill be notedrfromithe drawingsathe pin Bo -about :Which the .Wobbler: pivots is ofi center withrrespect: to 'the:central-longitudinal axis of the shafted!) and. with irespect i tothe Vi/701310181 faces \ThllS} as: shaft: l fii-isrota-ted: an -inertia. loads is applied to;thecvvobblerirtendin .to .rotate itabout theapi-votatoaapositiorr imparting maximum stroke? to the:pistonsi.; This=inertialload isiaugmented. by the Ahydraulic loadiapplied itol the pistons; as will 1 be hereinafter "described andr. thus the Wobbler" tendsato assume a :positiom causinga maximum: stroke with rotation 'of :the shaft" l 6 I Springs 34 are located in an: annular recess 35L betweennthe cylinder block-1 and' the casing I Bland. are'securedto an annular collar 36which'= in :tu'rn is' adapted to contact mowing 3'3 to urge" the WObbl'GIJtO neutral position; By compressing the --springs=-and '='thus' moving the collar 3 6' to the right r the Wobbler: assumes a stroke" imparting position as described. The springs may be compressed manually or, as in the embodiment shown, hydraulically. To this end I mount the springs in a sleeve 3'! slidable in the recess 35. The sleeve is provided with a shoulder 38 located in a chamber 39 formed between the sleeve and an annular member 40 secured to the casing iii. A fluid passage 4! is connected to the chamber 39 and to a main relay control valve 42 which is adapted to supply control fluid under pressure thereto to move the sleeve to the right to compress the springs. The control valve 42 forms no part of this invention and hence is not further described herein.

Each of the pistons M has a relatively larger portion 43 adjacent its left hand end (as seen in Fig. 1) and a relatively smaller portion 44 adjacent its right hand end. The cylinders l3 are so proportioned as to engage each of the sections of the piston and accordingly the right hand section 45 of each cylinder has a somewhat smaller diameter than the left hand end. The proportioning of the pistons provides an annular shoulder surface 43 on each piston to which oil pressure is applied to urge the pistons to the left on their intake strokes as hereinafter described.

\ The flow of fluid to and from the cylinders I3 is controlled by the valve device [8 which, as illustrated in the drawings, comprises a wheel-like member having a hub portion 41, an annular valving rim 48, and a plurality of openings 49 between the hub and the rim. The valve is psitioned with its annular rim portion 48 in the valve chamber 23 between the cylinder ports and the radially aligned discharge ports 20 opposite thereto. In order to reduce friction and wear on the valve 18 we prefer to pressurize the valve so as to cause it to bear against the discharge port face of the valve chamber 23. To this end the cylinder port face of the chamber is provided with a groove 50, which groove is in communication with high pressure oil from the piston ports. Oil pressure within the groove 50 serves to urge the valve against the discharge port face of the chamber, which face may be of bronze or other friction-reducing metal. The valve is given a gyratory movement by means of an eccentric pin 5! which is carried on a rotatable shaft 52 positioned in axial alignment with the shaft 16 and connected thereto by a spline arrangement 53.

The valve I8 is freely rotatable about the eccentric pin 5| and is provided with a perforated valving rim, the perforations taking the form of a plurality of openings 55 therethrough adapted to interconnect each of the cylinder ports with a predetermined different one of the discharge ports 20. In order to prevent cross-porting with rotation of the valve, the openings 55 through the rim are so proportioned as to have a diameter, measured circumferentially of the valving rim, less than the shortest distance between cylinder ports. The openings are located substantially on the circumference of a circle tangent to the cylinder ports at the valving line to high pressure, the valving line being determined by the eccentricity of movement of the valve and the piston circle in relation to the position of the Wobbler pivot. The optimum shape of the openings 55 is trapezoidal, as shown in Fig. 5, with the sides'55a and 55b of the trapezoid lying on radii of the valve. This is a diificult shape to machine and for purposes'of economy of manufacture we prefer to approach a trapezoidal shape through the medium of a plurality of :circular holes. Thus, the openings 55 comprise a first plurality of circular openings 56 arranged on the circumference of a circle concentric with the hub and a second plurality of smaller circular openings 5'5 lying on the circumference of a circle of smaller diameter than that of the openings 56. Two of the larger openings 56 are provided for each cylinder port and two of the smaller openings 51 are provided for each larger opening with alternate smaller openings intersecting and opening into a larger opening. Thus, the composite opening is somewhat trapezoidal in shape. In order to avoid trapping of fluid when one of the smaller openings 5? straddles a piston port, the circle on which the openings are located is approximately .010 inch smaller in diameter than the theoretical tangency to the cylinder port circle. The discharge ports 20 are located on a diameter so that a through passageway is obtained at the seal point. This arrangement eliminates the necessity of accurately aligning the discharge ports with the cylinder ports. To prevent leakage from the discharge ports to the inlet, the inner diameter of the valve plate on the discharge port face is made to provide a minimum of .060 seal. The discharge ports, therefore, are never exposed to the inlet. By the arrangement disclosed, rotation of the valve on its bearing pin 51 affects the discharge port area only slightly and the change in discharge velocity due to rotation of the valve is limited to approximately 5 to 10%.

The openings 49 permit flow of fluid from' the inlet it? to the cylinder ports on the suction stroke of the pistons in the usual manner.

In the particular embodiment shown eighteen pistons are provided in the pump which discharge into an equal number of of discharge ports 20. The end cap it is provided with a manifold ar rangement 59 designed to combine the eighteen discharge ports into six separate outlets by joining three ports equally spaced in the discharge port circle to form six groups of three discharge ports each. To this end the manifold is provided with six annular grooves 60 separated by 0 rings 6!. Slots 62 are milled in the manifold to connect each discharge port 20 to one of the six annular grooves 60.

Movement of the pistons on their return or suction stroke is accomplished by means of a gear pump 63 mounted upon the shaft 52 and conheated by means of a passage 64 to a groove 65 in each of the cylinders I3. The groove 65 is located at the mean position of the shoulder portion 38 and thus the pressure generated by the charge pump (33 serves constantly to urge the pistons to the left, that is, on their suction or return strokes.

We claim:

1. In a variable displacement hydraulic pump, a casing, a cylindrical valve chamber in the easing having parallel end faces, a plurality of fluid ports opening to one end face of the valve chamber in an annular row, a second plurality of fluid ports opening to the other end face of the valve chamber in an annular row, and a fluid passage opening to said valve chamber radially inwardly of said ports, a valve operable successively to connect the ports in the first mentioned end face alternately to the passage and to the other ports comprising a wheel-like member having a hub, a substantially circular valving rim and an opening between the hub and the rim, said rim having end faces in fluid-tight sliding engagement with the end faces of the valve chamber, means gamers engaging the hub for driving:-said valvelthrough an eccentricmovement with respecttosaidiports with the valve being permissibly rotatable in:.the chamber, and a plurality of openings extending through the valving rim and servingasjthe only means of communication between the ports in one end face and the ports in theother end face; the width or" each of said openingsimeasured circumferentially of the rim beinglessthan the shortest distance between the ports in: the first mentioned plurality;

2; In a Wobbler type hydraulic-pump or: motor, a casing, a cylindrical valve 'chamberin the case inghaving parallel end'faces, a'number ofpannularly arranged cylinders inthe casingwitlnea'ch cylinder having a port opening to one end face=of the valve chamber-to'form an annular-row of cylinderports, an equal number-of annularlyarranged ports opening to the other end face of the valve chamber'w-itlr each of the last-mentioned ports beingradially aligned-With acylinder port, anda fluid passage opening tosaidvalve chamber radially of said ports, a valve operable successively to connect the cylinder ports altei nately to the passage and to the other ports comprising a wheel-like member have a hub, a valving rim, said rim having end facesinfluidtight sliding engagement-With the end facesof the valve chamber, means engagingthehub for driving said valve through an eccentric-movement with respect to said ports with the valvebeing permissibly rotatable in the chamber, and a plurality of openings extending through the valving rim and acting, as passages for the flow of fluid between ports, said openings having awidth at the valving line measured circumferentially of the rim less thantheshortest circumferential distance between cylinder ports and being adapted to confine fluid flow between said portsto rae dially aligned ports. with eccentricmovementof the valve.

3. In a wobbler type hydraulic pump,a easing, a cylindrical valve chamber in thecasing having parallel end faces, a number of annularly arranged cylinders in the casing with each cylinder have a port opening to one end face of, thevalve chamber to form an annular row of cylinder ports, an, equal number of. annularly arranged dischargeportsjopeningito'the other end face of the valve chamber, and'a fluid passage opening to said valve chamber radially inwardly of said ports, a valve operable successively to connect the cylinder'ports alternately to the passage and to the discharge ports comprising a wheel-like mem her having ahub, a-substantially, circular valving rim and an opening betweenv the hub and the rim, said rim having end. faces in fluid-tightslid ing engagement with the.end"faces of thelvalve chamber, means engaging 'the hub for driving said valve through an eccentric movement with respect to said ports, a first plurality of circular openings through the rim and lying on a circle centered at the center of the hub, a second plurality of openings through the rim and smaller in diameter than the openings of the first plurality, said second plurality of openings lying on a circle concentric to and having a smaller diameter than the first circle, there being two large openings for each of the cylinder ports and there being two openings in the second plurality for each opening in the first plurality, with a small opening intersecting each large openin to form a composite opening, the diameter measured circumferentially of the rim of any of said 6 openings being less; than the shortesti distance betweencylinder ports.

41 Ina wobbler-type hydraulimpump; aw-casing; a cylindrical valve chamber in" the: casing having parallel end faces, anumber' of annularlyxar ranged cylinders in the .casingwith each cylinder having a; port opening to one end'faceof the valve chamber: to form anannular rowoficylincler ports, an equal number of. annularly arranged discharge ports opening to the: othersend face :of 171161 valve chamber: with each dischargezport being radially aligned. with .a cylinder port" and. a fluid passage opening tosaid" valve chamber rae dially inwardly, of'said ports, a. valve operable successively to connect the cylinder ports: alter:- nately to'thepassageiand to thedischargeiports comprising a wheelelike memberrhavingra .hub; ja valving 'rim and 1 an opening: between ,theihubi and the rim, said rimlhavingi end facestinfluid-tight sliding: engagement; with the ends faces; of? the valve chamber, means engaging the hub forzdrive ing said valve through an eccentricmovement withrespect to said portscand a plurality of 1013611: ings through the valving rim and adaptedto confinefluid flow from eachof said cylinder-s ports to its associated discharge port with eccentric movement of thevalve; saidlopeningslyings on the circumference .of alcirclentangentzto-saidtcyl+ inder ports at the valving point. to high: pressure; there being at least two :openingssfor 'eachiof: said cylinder ports;

5. In awobblertypephydraulic pump; a casing; a cylindrical valve. chamber .;the: casing having parallel end faces, a plurality ,of cylinder. ports opening to one; end facerof. the; valve chamber in an annular row, an .equalxnumberrofi discharge ports opening to theiother. endface ofthevalve chamber in an annular row,.and;a:fluid passage opening to said valve chamber radially inwardly of said. ports, a, valve operable, successively, to connect the cylinder ports, alternately to thepassage, and to. the, discharge ports. comprising a wheel-like member havinga hub,- a substantially circular valving rim and an openingbetween the hub and the rim, said rim having end facesiin fluids-tight sliding engagementwith the end faces of the valve chamber, means engagingthehub for'drivingsaidvalve through an eccentric move.- ment with respectto said port s,a: first plurality of circular openings through the rim and lying on a circlecentered at the. center ofnthe hub,,a second plurality of openings through .therimand smaller in diameter than the openings of the first plurality, said second plurality ofopenings lying: on acircle concentric to, and having a smaller diameter. than the first circle, ,there: be ingtwo larger openingsfor each ofsaid cylinder ports and there being two, smaller openings for each larger, opening witha small opening intersecting each largeopening to formacomposite single opening, the diameter measured circumferentially of the rim of any of said openings being less than the shortest distance between ports.

6. In a wobbler type pump having a casing, a cylindrical valve chamber in the casing having parallel end faces, a plurality of annularly arranged cylinders, a plurality of cylinder ports opening to the cylinders and to one end face of the valve chamber in an annular row, a plurality of fluid ports opening to the other end face of the chamber in an annular row, a fluid passage opening to said valve chamber radially inwardly of said ports, and a rotatable shaft for driving the wobbler relative to the cylinders, a

valveoperable. successivel to connect the cylin der ports alternately to the passage and to the other ports comprisin an eccentric on the shaft and extending. into said chamber, a wheel-like member having a hub and mounted on the eccentric, said member being permissibly rotatable in the chamber and having a substantially circular valving rim and an opening between the hub and the rim, and a plurality of substantially trapezoidal shaped openings through the valving rim, the width of said openings measured circumferentially of the rim being less than the shortest distance between the cylinder ports. 7

7. In a Wobbler type hydraulic pump, a casing a cylindrical valve chamber in the casing having parallel end faces, a number of annularly arranged cylinders in the casing with each cylinder having a port opening to one end face of the valve chamber to form an annular row of cylinder ports, an equal number of annularly arranged discharge ports opening to the other end face of the valve chamber, and a fluid inlet passage opening to said valve chamber radially inwardly of said ports, a valve operable successively to connect the cylinder ports alternately to the inlet passage and to the discharge ports comprising a wheel-like member having a hub, a substantially circular valving rim and an opening between the hub and the rim to connect the cylinder ports to the inlet, means engaging the hub for driving said valve through an eccentric move--v ment with respect to the ports'to move the valving rim radially outward sequentially to uncover the cylinder ports to permit fluid flow thereinto from the inlet passage, and a number of openings through the valving rim substantially in excess of the number of cylinders, said openings lyin on a circle centered at the center of the hub, the width of each of said openings measured circumferentially of the rim being less than the shortest 8. In a Wobbler type hydraulic pump or motor,

a" casing, a cylindrical valve chamber in the casing having parallel end faces, a number of annularly arranged cylinders in the casing with each cylinder having a port opening to one end face of the valve chamber to form an annular row of cylinder ports, an equal number of annularly arranged ports openin to the other end face of the valve chamber, and a fluid passage opening to said valve chamber radially inwardly of said ports, a valve operable successively to connect the cylinder ports alternately to the passage and to the other ports comprising a wheel-like member having a hub, a substantially circular valving rim and an opening between the hub and the rim to connect the cylinder 'ports to the passage, means engaging the hub for driving said valve through an eccentric movement with respect to the ports to move the valving rim radially outward sequentially to uncover the cylinder ports to permit fluid flow between the cylinder'ports and the passage, and a number of openings through the valving rim substantially in excess of the number of cylinders, said openings lying on a circle centered at the center of the hub, the width of each of said openings measured circumferentially of the rim being less than the shortest distance between cylinder ports and said openings being adapted to connect each of said cylinder ports separately and sequentially with a predetermined different one of said other ports with eccentric movement of the valve. 7

9. In a multiple outlet hydraulic pump, a casing, a cylindrical valve chamber in the casing having parallel end faces, a number of annular-1y arranged cylinders in the casing with each cylinder having a port opening to one end face of the valve chamber to form an annular row of cylinder ports, an equal number of annularly arranged discharge ports opening to the other end face of the valve chamber with each of the discharge ports being positioned opposite a dififerent one of the cylinder ports and a fluid inlet passage opening to said valve chamber radially of said ports, a valve operable successively to connect the cylinder ports alternately to the inlet passage and to the discharge ports comprising a wheel-like member having'a hub and a perforated valving rim, said rim having end faces in fluid-tight sliding engagement with the end faces of the valve chamber, means engaging the hub for driving said valve through an eccentric movement with respect to said ports with the valve permissibly rotatable in the valve chamber and with the perforations in the valving rim comprising a plurality of openings extending therethrough and acting as passages for longitudinal flow of fluid between each of said cylinderports and its opposed discharge port, said openings having a width at the valving line measured circumferentially of the rim less than the shortest circumferential distance between cylinder ports whereby to prevent annular fiow of fluid between the ports.

LUDWIG 'r. STOYKE. BRUCE H. MOSBACHER.

7 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,190,812 Wahlmark Feb. 20, 1940 2,383,093 Wahlmark Aug. 21, 1945 

